1. Install python and numpy
   2. Create input coma separated file with columns are in the order
Name,ra,dec,distance. 
   3. It is expected that you have cluster.dat, 2mass_group.dat,
sdss_group.dat, Karachentsev.dat catalogs in the same directory. 
   4. Run this script as python ScreeningThreadedAscii.py 
   5. This will ask for input catalog, output file name (default is
ScreenedOut.cat) and number of threads (default is 5)
   6. The output catalog has columns Name, ra, dec, distance to the
object, distance to the closest object, external potential with Compton
scale 10 Mpc (phi10), 8 Mpc ... 1 Mpc